Ruler



FIG. 1 is a front view of a ruler showing my new design;

FIG. 2 is a rear view thereof;

FIG. 3 is a top plan view thereof, the bottom plan view being identical;

FIG. 4 is a left side view thereof; and,

FIG. 5 is a right side view thereof.

CLAIM The ornamental design for a ruler, as shown and described.